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  1. #1
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    Default Installing A Thermal Overload

    Quick question.

    The motor on my Delta bandsaw burned out. I had it repaired and am in the process of reinstalling it in the machine. The repair shop gave me a thermal overload to install as well, but it did not come with instructions and I can't remember where they said to put it.

    Where should the thermal overload be installed, before or after the on/off switch?
    Last edited by A. Spruce; 07-21-2012 at 08:16 PM. Reason: Clarification of the question
    I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!

  2. #2
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    Default Re: Installing A Thermal Overload

    Isn't it a safety issue, like a fuse? then it should go between the power and the motor. Do I make sense to you?

  3. #3
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    Default Re: Installing A Thermal Overload

    Or, give the repair shop a call.

  4. #4
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    Default Re: Installing A Thermal Overload

    Looking ****** for a wiring diagram I've not found one for a 120v O/L protector. The one I was give only has two contacts.


    You're saying that the O/L should be placed before the motor on the incoming power cord, correct?

    It's Saturday, the shop is closed.
    Last edited by A. Spruce; 07-21-2012 at 07:21 PM.
    I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!

  5. #5
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    Default Re: Installing A Thermal Overload

    logically, yes: between the power supply and the motor.

  6. #6
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    Default Re: Installing A Thermal Overload

    Ok, if it's wrong, it's YOUR fault!
    I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!

  7. #7
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    Default Re: Installing A Thermal Overload

    Worst case scenario: you'll have to call the fire dept. They're open on Saturday.

  8. #8
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    Default Re: Installing A Thermal Overload

    A friend just pointed out some silliness, which got me to thinking and to revise the question. I was thinking about the junction box mounted to the side of the motor and all connections being made there, which isn't how things work. What I needed to do was be thinking of the flow of power, which is "line-switch-load", which consequently made me revise the question to:

    Where should the thermal overload be installed, before or after the on/off switch?

    Which now that I've had all this time to think and type about it makes the question pretty darned silly! Now all I have to do is find my wire clamps so that the power cord can't be yanked and damage the O/L.

    And DJ, if the fire department comes a calling, I'll be sure to send them your way.
    I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!

  9. #9
    Join Date
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    251

    Default Re: Installing A Thermal Overload

    IF you think about it, it doesn't matter. IT's a complete circuit regardless. But I've always seen overload after the contacts on a contractor. In this case, there's just a on/of switch not contacts.


    For some clarification. A breaker protects the wire, primarily in the branch circuit against peak currents. A overload, is a device that protects the motor against sustained high currents to protect the motor insulation from thermal failure.

    Large motors with straight line starters usually have a contractor (which is just a big relay) along with a manually or remotely resetable circuit breaker and thermal overloads.
    1925 Two-Story Stucco Beaux Arts Neoclassical

  10. #10
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    Default Re: Installing A Thermal Overload

    Spruce, a good place will be between the motor and the switch.

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